Electrical switch



Feb. 11, 1930. K. M. STRAND ELECTRICAL SWITCH 2 Sheets-Sheet 1 Filed Nov. 1'7, 1926 IW Mk mrak.

Feb. 11, 1930. I KQM. STRAND 1,746,370

ELECTRICAL SWITCH Filed Nov. 17, 1926 2 Sheets--$heet 2 Patented Feb. 11, 1930 KNUT MADSEN STRAND, on DRMEIVIEN, NORWAY ntnorarear. swrroia application filed November 17, 1926, Serial No. 148,919, and in Norway November 23, 1925.

This invention relates to that type of electrical switches in which the contact-blade is so connected with its operating means that, in breaking the circuit, the blade is first I moved-along the contact springs and then describes an angular movement, whereas the closing of the circuit is effected by a rectilinear movement following an angular movement of the blade.

The novelty of the inventionconsists in providing controlmechanism for the movable blade carrier that moves the latter longitudinally thereof, and prevents longitudinal movement during'the angular movement of the blade and vice versa.

Various constructional forms of said mech-' anism are possible, but in order that the in vention may be understood two of these are illustrated, by way of example, on the accompanying drawing to which reference will now be made and whereon Fig. 1 is a side elevation of a' switch in accordance with the invention.

Fig. 2 is a part plan corresponding to Fig. 3 is a side elevation, partly in section, showing the mechanism for efiecting the combined longitudinal and angular movements of the blade carrier. 1

gig. t is a plan corresponding to Fig. 3, an

' Fig. 5 shows, in side elevation and part section, a second or modified form of the operating mechanism.

Figs. 6 and 7 show further modifications.

On the drawing, 1 denotes the frame on which the switch is mounted, 2, 3 and 4 the insulating pillars supporting the various switch members, 5 the contact-springs supattached a head 22 adapted to be turned in a ported by the pillar 2, 6 the contact-blade,

horizontal plane. Said head is pivotally connected to a rod 13, so that the rod can swing in a vertical plane. By means of a second head 12, the rod is connected to a crank arm 11 keyed on a shaft 25 which is rigidly attached to the blade carrier 7. The shaft 25 50 is journalled in a slide 10 arranged to work in guides 14 in a support 9. Said slide has a stop 15 with an oblique forward end adapted to co-act, with a latch 18, on an arm 16 pivoted on a bracket 17 and controlled by a spring 19.

With the parts in the position shown, the switch is closed. If now, the operating shaft 21 be turned clockwise (Fig. 4) the crank-pin I 23, head 22 etc. move as indicated by the dotted lines, thereby causing the slide 10 and therefore the carrier 7 for the contact-blade to move horizontally to the right until the stop 15 trips past the latch 18 and projections 11 on the crank pin bear against the pin 20 on the locking arm 16. No further horizontal movement of the slide can then take place, but during the continued turning movement of the operating shaft the crank 11 and shaft 25 are turned, so that the carrier 7 and contact-blade receive the necessary angular movement.

The angle of the crank 11 is such that under thepull of the rod 13 it necessarily moves the slide until the projection 11* comes against the pin 20.

On .the shaft 21 being turned back, the crank 11 and shaft 25 are also turned to impart an angular movement to the carrier 7 and blade 6 in the reverse direction, but the latch 18 prevents any horizontal movement of the slide 10 until the projections 11 have lifted the latch out of engagement with the stop 15, whereupon a horizontal movement of the slide etc. ensues back to the original position, that is to say, the contact-blade is first swung into the horizontal position and then thrust lengthwise between the contact springs.

According to Fig. 5, the crank arm 11 is connected to a wiper 26. Said wiper is pro vided with a curved portion 28 and a straight portion 29 with which a roller 27 on the arm 16 makes contact. On the rod 13 being moved towards the right to open the switch, the portion 29 is in contact with the roller 27 and prevents any angular movement of the crank pin 11 and therefore of the carrier 7 for the contact-blade 6. During a continuation of prevented, and a positive rotational move ment is imparted to the crank pin 11 and consequently to the carrier 7 for the contactblade 6, the surface 28 moving over the roller 27 until, as indicated bythe broken lines, the

surface 29 of the wiper 26 bears against a vertical surface of the support 9.

Durin the return movementof the rod 13 to close t e switch, a positively guided swinging movement is first imparted to the crank pin 11, followed by a horizontal movement of same, .so that the blade 6 is first turned into a horizontal position and is then thrust in the horizontal direction between'the contact springs 5.

According to Fig. 6 the stopping and controlling device is constructed in such a way that the horizontal motion is limited by a surface 28A contacting with the roller 27 placed upon a support 34 carried by a portion 9 similar'to that shown in Fig. 5. 31 denotes an arm carrying a stopping screw 32 coacting with a stop 33 and adapted for adjusting the an lar motion of the device.

ig. 7 shows a construction substantiall similar to that shown in Fig. 6 the only di ference consisting therein that a groove is arranged in the stopping and controlling device embracin the roller,27 so that any free 40 motion of the device is prevented. The groove is provided with rounded connecting surfaces 29" and 29 between the straight portion and the curved portion of the guide.

It will be understood that an electrical switch according to this invention makes neo-. essary grindin of the contacts against each other possible by means of the usualoperating handle or mechanical appliances without interrupting the working. For such purpose the breakmg handle may be provided 7 with a rigid arch upon which the handle is moved during the angular motion between the outermost positions. Such arch may be provided with stops by means of which the andle 15 secured in its positions for openmg and breaking the circuit.

Further an adjustable stop is provided by means of which the operating handle may be moved forward and backward in such a wa that the contact blade receives a longitu inal motion limited so that a breaking of the circuit is avoided.

' It Wlll now be evident that also other modifications are possible without departing from the scope of the invention. For example,

a crank on the shaft, operating means con-' nected with the crank, a stationary sto and means movable with the slide under t e action of the operating means to engage the stop whereafter the operating means acts to turn the shaft in the slide.

2. In an electrical switch the combination of stationary contacts, a co-acting movable contact-blade, a carrier for the blade, a shaft on which the carrier is secured, a slide in which the shaft is journalled, a crank on the shaft, operating means connected with the crank, a stationary'stop, means movable I with the slide under the action of the operating means that opens the switch to engage the stop whereupon the-sliding movement ceases and the shaft is turned, and means for freeing the slide after a redetermined turning movement of the shaft in the opposite direction under the action of the operating means that closes the'switch.

3. In an electrical switch the combination of stationary contacts, a co-acting movable contact-blade, a carrier for the blade, a shaft on which the carrier is secured, a slide in which the shaft is journalled, a crank on the shaft, operating means connected with the crank, a latch projecting into the path of the slide, a stop on the slide to engage the latch under the action of the operating means that opens the switch whereupon the sliding movement ceases and the shaft is turned, and

' means on the crank to lift the latch and free the slide after a predetermined angular movement of the shaft in the opposite direction under the action of the operating means that closes the switch. a

4. In an electricalswitch the combination of stationary contacts, a co-actin movable contact-blade, a carrier for the bla e, a shaft on which the carrier is secured, a slide in which the shaft is journalled, a crank on the shaft, an operating disc, a crank pin on the disc, a head turnable on the pin, a connecting rodpivotally connected at one end to the head and at its other end to the aforesaid crank, a stationary stop, and means movable with the slide to engage said stop during movement of the operating disc to open the switch. I

5. In an electric switch-the combinationof stationary contacts, a oo-acting movable conmaaavo tact-bladefa carrier for the blade, a shaft on stop during movement which the carrier is secured, a slide in which the shaft is j ournalled, a crank on the shaft, an operating disc, a crank pin on the disc, a head turnable on the pin, a connecting rod pivotally connected at one end to the head and at its other end to the aforesaid crank, a stationary stop, means movable with the slide to engage said stop during movement of the operating disc in a direction to open the switch and means on the aforesaid crank to free the slide again during movement of the operating disc in a direction to close the switch.

6. In an electrical switch the combination of a frame, insulating pillars on the frame, resilient contact. jaws on one of the pillars, a co-actin contact-blade, a movable carrier for the blade, a housing supported by the remaining pillars, a slide within the Housing, a shaft journalled in the slide on which shaft the carrier is secured, a crank on the shaft, operating means connected with the crank, a stationary stop, means movable with the slide under the action of the operating means that opens the switch to engage the stop whereupon the sliding movement ceases and the shaft is turned, and means for freeing the slide after a predetermined turning movement of the shaft in the opposite direction under the action of the operating means that closes the switch.

7. In an electrical switch the combination of a frame, insulating pillars on the frame,

' resilient contact aws on one of the pillars, a

co-acting contact-blade, a movable carrier for the blade, a housing supported by the remaining pillars, a slide within the housing, a shaft on which the carrier is secured journalled in the slide, a crank on the shaft, operating means connected with the crank, a spring-pressed latch projecting into the path of the slide, a stop on the slide to engage the of the operating disc to open the switch.

9. In an electrical switch the combination 7 of a frame, insulating pillars on the frame, resilient contact jaws on one of the pillars a coacting contact-blade, a movable carrier or the blade, a housing supported by the remaining pillars, a slide within the housing; a shaft journalled in the slide on which shaft the carrier is secured, acrank on'the shaft, an operating disc, a crank pin on the disc, a head turnable on the pin, a rod pivotally connected at one end to the head and at its other end to the aforesaid crank, a stationary stop, means movable with the slide to engage the stop when the operating disc is turned to open the switch, and means on the aforesaid crank to free the slide again after a predetermined movement of the operating disc in a direction to close the switch.

V 10. In an electrical switch the combination of a frame, insulating pillars on the frame, resilient contact jaws on one of the pillars a coacting contact blade, a movable carrier or the blade, a housing supported by the remaining pillars, a slide within the housing, a shaft journalled in the slide on which shaft the carrier is secured, a crank on the shaft, an operating disc, a crank pin on the disc, a head turnable on the pin, a rod pivotally connected 9 at one end to the head and at its other end to the aforesaid crank, means movable with the slide for controlling the position of the crank during the motion of the slide and preventing any uncontrolled motion of the same.

In testimony whereof I aflix my signature.

KNUT MADSEN STRAND.

latch under the action of the operating means that opens the switch whereupon the sliding movement ceases and the shaft is turned, and

means on the crank to lift the latch and free the slide after a predetermined angular movement of the shaft in the opposite direction under the action of the operating means that closes the switch.

8. In an electrical switch the combination of a frame, insulating pillars .on the frame, resilient contact-jaws on one of the pillars, a

co-acting contact-blade,a movable carrier for the blade, a housing supported by the remaining pillars, a slide within the housing,a shaft journalled in the, slide on which shaft the carrier is secured, a crank on the shaft, an operating disc, a crank pin on the disc, a head turnable on the pin, a rod pivotally connected at one end to the head and at its other end to the aforesaid crank, a stationarystop, and

means movable with the slid-"to"eng'age the 

